feat!: add xsdata models

[afuetterer]

Refs: Fixes #126, fixes #152, fixes #111

Tasks

Add description of mapping
Tuple unpacking for usage of mapping

• update Response class, compare python-re3data, see https://github.com/afuetterer/python-re3data/blob/main/src/re3data/_response.py
• remove repr=false in response
• add readme.md to models directory about model generation with xsdata cli
• remove readme.md and xml from wheel
• make oai_pmh and oai_dc modules instead of packages, compare python-re3data, see https://github.com/afuetterer/python-re3data/tree/main/src/re3data/_resources
• Resolve merge conflicts
• Update xsdata version
• Truncate models in docs output
• add xsdata models for "oai_pmh" xsd
• add xsdata models for "oai_dc" xsd
• add Response dataclass
• add _build_response() helper function
• add _parse_response() helper function
• remove obsolete get_namespace() helper function
• remove obsolete xml_to_dict() helper function
• tests are passing
• Fix OAI-PMH specific error handling #152
• Add tests for error codes #111
• Deleted status mixin for header and record
• xsdata in readme
• mock response needs content -> fixture with identify xml
• Encoding was set on response
• Add url attr to response
• mypy is passing (3 issues remaining)
• Example oai dc, datacite
• update docs
  • customizing
  • check if returns and yields sections are displayed twice under api/client/
  • nested api reference for models
• Show example of response without known metadata format, e.g. "arxiv"
• Check if save to xml.code still works, uses raw

Refs:

• https://xsdata.readthedocs.io/en/latest/codegen.html

[afuetterer]

Commit message draft:

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feat!: add xsdata models

body

Refs: Fixes #126, fixes #152, fixes #111

[afuetterer]

Lets start with only oai dc and oai pmh. No datacite, no marc etc.